US7557566B2 - Method and apparatus for measurement of magnetic permeability of a material - Google Patents

Method and apparatus for measurement of magnetic permeability of a material Download PDF

Info

Publication number
US7557566B2
US7557566B2 US11/681,258 US68125807A US7557566B2 US 7557566 B2 US7557566 B2 US 7557566B2 US 68125807 A US68125807 A US 68125807A US 7557566 B2 US7557566 B2 US 7557566B2
Authority
US
United States
Prior art keywords
coil
sample
magnetic
fluid
magnetic permeability
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active, expires
Application number
US11/681,258
Other languages
English (en)
Other versions
US20080214092A1 (en
Inventor
William Kordonski
Arpad Sekeres
Robert James
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
QED Technologies International LLC
Original Assignee
QED Technologies International LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by QED Technologies International LLC filed Critical QED Technologies International LLC
Priority to US11/681,258 priority Critical patent/US7557566B2/en
Assigned to QED TECHNOLOGIES INTERNATIONAL, INC. reassignment QED TECHNOLOGIES INTERNATIONAL, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: JAMES, ROBERT, KORDONSKI, WILLIAM, SEKERES, ARPAD
Priority to PCT/US2008/055053 priority patent/WO2008109301A1/en
Priority to JP2009551811A priority patent/JP2010520456A/ja
Priority to CN200880006869A priority patent/CN101622548A/zh
Priority to US12/449,655 priority patent/US7888929B2/en
Publication of US20080214092A1 publication Critical patent/US20080214092A1/en
Application granted granted Critical
Publication of US7557566B2 publication Critical patent/US7557566B2/en
Assigned to BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT reassignment BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT NOTICE OF SECURITY INTEREST IN PATENTS Assignors: CABOT MICROELECTRONICS CORPORATION
Assigned to JPMORGAN CHASE BANK, N.A. reassignment JPMORGAN CHASE BANK, N.A. SECURITY AGREEMENT Assignors: CABOT MICROELECTRONICS CORPORATION, FLOWCHEM LLC, KMG ELECTRONIC CHEMICALS, INC., MPOWER SPECIALTY CHEMICALS LLC, QED TECHNOLOGIES INTERNATIONAL, INC.
Assigned to CABOT MICROELECTRONICS CORPORATION reassignment CABOT MICROELECTRONICS CORPORATION RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: BANK OF AMERICA, N.A.
Assigned to QED TECHNOLOGIES INTERNATIONAL, INC., MPOWER SPECIALTY CHEMICALS LLC, FLOWCHEM LLC, CABOT MICROELECTRONICS CORPORATION, CMC MATERIALS, INC., INTERNATIONAL TEST SOLUTIONS, LLC, KMG ELECTRONIC CHEMICALS, INC., KMG-BERNUTH, INC., SEALWELD (USA), INC. reassignment QED TECHNOLOGIES INTERNATIONAL, INC. RELEASE OF SECURITY INTEREST Assignors: JPMORGAN CHASE BANK, N.A.
Assigned to MORGAN STANLEY SENIOR FUNDING, INC., AS COLLATERAL AGENT reassignment MORGAN STANLEY SENIOR FUNDING, INC., AS COLLATERAL AGENT SECURITY INTEREST Assignors: CMC MATERIALS, INC., INTERNATIONAL TEST SOLUTIONS, LLC, QED TECHNOLOGIES INTERNATIONAL, INC.
Assigned to TRUIST BANK, AS NOTES COLLATERAL AGENT reassignment TRUIST BANK, AS NOTES COLLATERAL AGENT SECURITY INTEREST Assignors: CMC MATERIALS, INC., ENTEGRIS GP, INC., ENTEGRIS, INC., INTERNATIONAL TEST SOLUTIONS, LLC, POCO GRAPHITE, INC., QED TECHNOLOGIES INTERNATIONAL, INC.
Assigned to FIDUS INVESTMENT CORPORATION reassignment FIDUS INVESTMENT CORPORATION SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: QED TECHNOLOGIES INTERNATIONAL, INC.
Assigned to QED TECHNOLOGIES INTERNATIONAL, INC. reassignment QED TECHNOLOGIES INTERNATIONAL, INC. PARTIAL RELEASE OF SECURITY INTEREST IN INTELLECTUAL PROPERTY RECORDED AT REEL 060613, FRAME 0072 Assignors: TRUIST BANK, AS NOTES COLLATERAL AGENT
Assigned to QED TECHNOLOGIES INTERNATIONAL, INC. reassignment QED TECHNOLOGIES INTERNATIONAL, INC. PARTIAL RELEASE OF SECURITY INTEREST Assignors: MORGAN STANLEY SENIOR FUNDING, INC., AS AGENT
Active legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
    • B24B1/005—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes using a magnetic polishing agent
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
    • G01N27/74—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables of fluids
    • G01N27/76—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables of fluids by investigating susceptibility

Definitions

  • the present invention relates to methods and apparatus for inferential measurement; more particularly, to methods and apparatus for determining the magnetic permeability of a material; and most particularly, to a method and apparatus for using such measurement to control the concentration of a magnetic material in a magnetorheological (MR) fluid.
  • MR magnetorheological
  • MR fluids are well known and may be defined practically as fluid materials whose apparent viscosities are reversibly increased by exposure of the fluid to a magnetic field.
  • the increase in viscosity is anisotropic, being greatest in the direction of the magnetic field due to formation of fibrils of magnetized particles.
  • This property known in the art as “stiffening”, has been employed to great success in the field of extremely high resolution shaping, finishing, and polishing of surfaces, especially optical elements, wherein very small amounts of material may be removed in a highly precise and controlled manner.
  • This field is known generally in the art as magnetorheological finishing (MRF). See, for example. U.S. Pat. Nos. 5,971,835; 6,746,310; and 6,893,322, the relevant disclosures of which are incorporated herein by reference.
  • MR fluid is supplied to the work zone by a delivery system that draws MR fluid from a mixing sump into which used MR fluid passes from the work zone for mixing and reuse.
  • the used MR fluid typically is depleted in carrier (water) by evaporation and also is heated, both of which alterations must be corrected before the MR fluid may be reused. Without replenishment of water lost to evaporation, the bulk supply of MR fluid in the sump will gradually increase in particle concentration during an MRF operation. This is an undesirable operating condition because particle concentration is an important factor governing the rate of removal of material from a substrate being finished.
  • U.S. Pat. No. 5,554,932 discloses a system for measuring magnetic saturation flux density of a sample material.
  • First and second sample holders are disposed symmetrically on either side of a cylindrical permanent magnet. Coils are placed around the sample holders and the permanent magnet is rotated. The signals induced in the coils in the absence of a magnetic material in one of the sample holders are applied to an amplifier/meter in such a manner as to provide a null signal. When a sample is placed in one of the sample holders, the magnetic saturation flux density can be measured.
  • a shortcoming of the disclosed system is that the mechanical device is relatively cumbersome and has a critical moving part (the permanent magnet).
  • U.S. Pat. No. 6,650,108 discloses a system for inferring concentration of magnetic particles in a flowing MR fluid.
  • the system is based on inductance measurement that converges in an impedance measurement with relatively complex technique involving high sensitivity electric bridge circuits.
  • a shortcoming of the disclosed system is that resolution is relatively low.
  • two electrical inductors share the same magnetic core.
  • the inductors are formed as primary and secondary concentric coils.
  • an AC voltage is applied to the primary coil, an axially-directed magnetic flux is created in the core which is proportional in intensity to the magnetic permeability of the core.
  • the magnetic flux induces an AC voltage in the secondary coil which is in phase with the source voltage.
  • the magnetic permeability of the core depends upon the concentration of magnetic particles in the sample (when the “core” is a sample of MR fluid), and this the concentration of magnetic particles can be back-calculated from the amplitude of the secondary voltage signal.
  • Sensitivity of measurements and system resolution can be increased by using a differential approach using two identical sets or pairs of coils wherein a reference material forms a magnetic core for one coil set and the MR fluid forms a magnetic core for the other coil set.
  • FIG. 1 is a schematic drawings of a first embodiment of a system in accordance with the invention for measuring magnetic permeability
  • FIG. 2 is a schematic drawings showing the first embodiment in use in an MR fluid
  • FIG. 3 is a calibration curve for the first embodiment showing the relationship between output voltage and concentration of magnetic particles in an MR fluid
  • FIG. 4 is a calibration curve for the first embodiment showing the relationship between moisture percentage and concentration of magnetic particles in an MR fluid
  • FIG. 5 is a schematic drawing showing application of the first embodiment to an MRF system.
  • FIG. 6 is a schematic drawing of a second embodiment of a system in accordance with the invention.
  • a system 10 in accordance with the invention suitable for measuring the magnetic permeability of the material of a magnetic core 12 , two inductors (primary coil 14 and secondary coil 16 ) share magnetic core 12 , which is a sample of a magnetic material, such as MR fluid, to be tested.
  • primary coil 14 and secondary coil 16 share magnetic core 12 , which is a sample of a magnetic material, such as MR fluid, to be tested.
  • V s 4.44 ⁇ ⁇ ⁇ ⁇ ⁇ f ⁇ N 2 ⁇ A l ⁇ I p ( Eq . ⁇ 3 )
  • Primary coil 14 behaves as a load with respect to the AC voltage source V p
  • secondary coil 16 behaves as a source with respect to resistor R 2 .
  • V s f ( ⁇ , k 1 , k 2 . . . ) (Eq. 5) where k 1 , k 2 . . . are some constant parameters which depend on system geometry and system electrical parameters.
  • the magnitude of output signal can be manipulated by (pre) setting the different system parameters such as number of turns and geometries of the coils, frequency and voltage of the oscillator, impedance of the components, and the like.
  • System 10 further may contain a temperature sensor (not shown), such as a thermistor, and means to compensate for thermal variation in circuit impedance and change in output signal due to variations of temperature.
  • a quantitative relationship between the concentration and the voltage V s in secondary coil 16 is determined by calibration with samples of known magnetic particles concentration.
  • an exemplary embodiment 110 for measuring magnetic permeability of an MR fluid 120 is a vessel 122 , primary and secondary coils 114 , 116 of a double-coil sensor unit 119 are encapsulated in a waterproof case 124 material and a wand 126 carrying electrical leads (not shown) is provided to submerge the coils in MR fluid 120 which fills sample cell 128 within the coils, thereby defining the magnetic core of the system. Measurement is then made as described below.
  • FIGS. 3 and 4 samples of water-based MR fluid were used for testing and system calibration.
  • each coil had 200 turns, and the AC frequency of primary voltage V p was 1000 Hz.
  • Moisture (amount of water), which defines the concentration of magnetic particles, was measured with Moisture Analyzer HB43, available from Mettler-Toledo Gmbh, Switzerland.
  • FIGS. 3 and 4 show an excellent linear dependence of concentration on voltage and moisture, respectively, in the range of measured concentrations, as predicted by Equation 6.
  • FIG. 5 an exemplary application is shown for a system 210 in accordance with the present invention in assisting in maintaining a constant concentration of magnetic particles in MR fluid in an MR finishing apparatus 200 .
  • a carrier wheel 230 has a surface 232 , preferably spherical, for receiving a ribbon 234 of MR fluid in a non-stiffened state from nozzle 236 .
  • Shaped magnetic pole pieces (not shown) create an orientated magnetic field within work zone 238 that causes the MR fluid therein to become stiffened to a consistency approximating putty.
  • the stiffened MR fluid which may also contain non-magnetic particles of abrasives such as cerium oxide, ablates the surface of work piece 240 in controlled fashion as it is drawn through work zone 238 .
  • Carrier surface 232 continuously supplies and removed MR fluid to and from work zone 239 .
  • a scraper 242 removed used MR fluid, no longer stiffened, from carrier surface 232 and returned it via a suction pump 244 to a mixing sump 246 , wherein the used MR fluid is mixed with a bulk supply of MR fluid 220 and from whence mixed MR fluid 220 is drawn by delivery pump 248 and supplied again to nozzle 236 via non-magnetic tube 250 .
  • a double-coil mutual inductance sensor 219 in accordance with the present invention and controllably driven by an AC power supply 252 as described above is placed concentrically outside non-magnetic tube 250 filled with flowing MR fluid 220 .
  • Sensor 219 provides in-line measurement/monitoring of concentration of magnetic particles in MR fluid 220 flowing through the sensor.
  • An output signal 254 is directed to a programmable controller 256 , programmed in accordance with FIGS. 3 and 4 and having a set point corresponding to an aim concentration, which controls a pump 258 to dispense replenishment water 260 into sump 246 at a controlled flow rate to compensate for water evaporated from the MR fluid ribbon 234 when exposed on carrier wheel 230 during use thereof.
  • Replenishment water 260 is mixed with the bulk supply MR fluid within sump 246 to dilute the bulk concentration to aim.
  • concentration of magnetic particles in MR fluid 220 as drawn from sump 246 for supply to work zone 238 is maintained at the aim concentration, providing a stable and predictable rate of material removal from work pieces 240 .
  • sensitivity of measurements and system resolution can be increased using a differential approach/methodic.
  • two identical sets 319 a and 319 b of coil pairs are used.
  • First coil set 319 a surrounds a magnetic core sample 312 a to be tested
  • coil set 319 b surrounds a core sample 312 b of a reference material with known magnetic permeability, for example, air.
  • first and second coil sets are arbitrary, as the sets are identical; either one may be the sample set, the other the reference set.
  • Both primary coils 319 a p , and 319 b p are connected to AC voltage source (oscillator) 352 in parallel.
  • Secondary coils 319 a s , 319 b s are connected in series but are wired so that currents Is 1 , Is 2 of the secondary coils are oppositely directed through resistance R 2 ; thus, the resulting current will be equal to zero when the same samples or no samples are placed inside the coils.
  • System 300 obviously may contain some additional common means (not shown) to accurately balance the system when, for example, sample 312 a is an MR fluid of the correct magnetic permeability.
  • second embodiment 310 shows improved sensitivity and resolution over the first embodiment 210 , implementation thereof can be somewhat more complex and expensive; ergo, first embodiment 210 may be a satisfactory choice for MRF applications.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Biochemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
  • Constituent Portions Of Griding Lathes, Driving, Sensing And Control (AREA)
US11/681,258 2007-03-02 2007-03-02 Method and apparatus for measurement of magnetic permeability of a material Active 2027-06-09 US7557566B2 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US11/681,258 US7557566B2 (en) 2007-03-02 2007-03-02 Method and apparatus for measurement of magnetic permeability of a material
PCT/US2008/055053 WO2008109301A1 (en) 2007-03-02 2008-02-27 Method and apparatus for measurement of magnetic permeability of a material
JP2009551811A JP2010520456A (ja) 2007-03-02 2008-02-27 材料の透磁率を測定するための方法および装置
CN200880006869A CN101622548A (zh) 2007-03-02 2008-02-27 用于测量材料的磁导率的方法和装置
US12/449,655 US7888929B2 (en) 2007-03-02 2008-02-27 Method and apparatus for measurement of magnetic permeability of a material

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US11/681,258 US7557566B2 (en) 2007-03-02 2007-03-02 Method and apparatus for measurement of magnetic permeability of a material

Related Child Applications (2)

Application Number Title Priority Date Filing Date
US12/449,655 Continuation US7888929B2 (en) 2007-03-02 2008-02-27 Method and apparatus for measurement of magnetic permeability of a material
US12/449,655 Continuation-In-Part US7888929B2 (en) 2007-03-02 2008-02-27 Method and apparatus for measurement of magnetic permeability of a material

Publications (2)

Publication Number Publication Date
US20080214092A1 US20080214092A1 (en) 2008-09-04
US7557566B2 true US7557566B2 (en) 2009-07-07

Family

ID=39733432

Family Applications (2)

Application Number Title Priority Date Filing Date
US11/681,258 Active 2027-06-09 US7557566B2 (en) 2007-03-02 2007-03-02 Method and apparatus for measurement of magnetic permeability of a material
US12/449,655 Active 2027-03-26 US7888929B2 (en) 2007-03-02 2008-02-27 Method and apparatus for measurement of magnetic permeability of a material

Family Applications After (1)

Application Number Title Priority Date Filing Date
US12/449,655 Active 2027-03-26 US7888929B2 (en) 2007-03-02 2008-02-27 Method and apparatus for measurement of magnetic permeability of a material

Country Status (4)

Country Link
US (2) US7557566B2 (en].)
JP (1) JP2010520456A (en].)
CN (1) CN101622548A (en].)
WO (1) WO2008109301A1 (en].)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090267596A1 (en) * 2008-03-07 2009-10-29 California Institute Of Technology Effective-inductance-change based magnetic particle sensing
US20100101309A1 (en) * 2008-10-23 2010-04-29 Simone Klyamkin System and method for measuring the concentration of magnetic ballast in a moving slurry
EP2697017A4 (en) * 2011-04-13 2014-10-01 Qed Technologies Int Inc METHOD AND DEVICE FOR MEASURING AND CONTROLLING THE CONCENTRATION OF MAGNETIC PARTICLES IN A MAGNETORHEOLOGIC LIQUID
US20150233867A1 (en) * 2012-09-26 2015-08-20 Evoqua Water Technologies Llc System for Measuring the Concentration of Magnetic Ballast in a Slurry
US9599591B2 (en) 2009-03-06 2017-03-21 California Institute Of Technology Low cost, portable sensor for molecular assays

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9328276B2 (en) * 2010-05-03 2016-05-03 Chemtreat, Inc. Method and apparatus for improving heat transfer in industrial water systems with ferrofluids
CN102230872A (zh) * 2010-06-01 2011-11-02 鞍钢集团矿业公司 在线检测流动矿浆的磁性铁品位的装置及其检测方法
CN102654538A (zh) * 2011-03-03 2012-09-05 重庆师范大学 基于磁流变体智能传感技术的磁流变(液)阻尼器健康在线自诊断检测方法与装置
CN102873592B (zh) * 2012-09-11 2015-09-16 青岛佳普智能材料应用有限公司 基于换能装置的表面光整加工装置
DE102012219242A1 (de) * 2012-10-22 2014-04-24 Rolls-Royce Deutschland Ltd & Co Kg Messvorrichtung und -verfahren zur Detektierung ferromagnetischer Partikel
JP5775049B2 (ja) * 2012-10-25 2015-09-09 ＡｖａｎＳｔｒａｔｅ株式会社 ガラス基板の製造方法
CN103018144A (zh) * 2012-11-13 2013-04-03 重庆绿色智能技术研究院 诊断电路、磁流变液诊断装置以及自诊断磁流变液阻尼器
CN103244600B (zh) * 2013-05-31 2014-12-03 山东理工大学 汽车磁流变半主动悬架电磁线圈匝数的设计方法
CN104034455B (zh) * 2014-07-01 2016-01-06 重庆材料研究院有限公司 基于磁流变材料的压力传感器
CN105983480A (zh) * 2015-02-27 2016-10-05 丹东东方测控技术股份有限公司 一种实时测量磁力脱水槽精矿层位置的方法
CN107153093A (zh) * 2016-03-04 2017-09-12 中国石油化工股份有限公司 一种用于测量模拟储层的磁导率的系统及方法
CN106826401B (zh) * 2016-07-25 2019-01-22 中国科学院长春光学精密机械与物理研究所 一种磁流变抛光面形误差收敛控制加工方法
DE202017103847U1 (de) * 2017-06-28 2017-07-21 Airbus Operations Gmbh System zur Führung eines Roboters durch eine Passagierflugzeugkabine
KR102283396B1 (ko) * 2019-12-30 2021-07-28 조선대학교산학협력단 와전류 비파괴검사를 위한 센서프로브 검사장치
CN113352152B (zh) * 2020-02-20 2022-12-06 中国科学院长春光学精密机械与物理研究所 一种基于机械臂的磁流变抛光加工系统
KR102456992B1 (ko) * 2022-02-28 2022-10-21 주식회사 씨케이머티리얼즈랩 자기유변유체의 특성 평가 방법

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2790950A (en) * 1954-02-24 1957-04-30 United States Steel Corp Determining the permeability of magnetic material
USRE34039E (en) * 1985-09-30 1992-08-25 Kabushiki Kaisha Toshiba Torque sensor for detecting a shaft torque and an electric machine in which the torque sensor is mounted
US5554932A (en) 1993-12-17 1996-09-10 Eastman Kodak Company Measurement of a saturation magnetic flux density through use of a rotating permanent magnet
US5971835A (en) 1998-03-25 1999-10-26 Qed Technologies, Inc. System for abrasive jet shaping and polishing of a surface using magnetorheological fluid
US20030020463A1 (en) * 2001-05-11 2003-01-30 Lord Corporation System and method for monitoring the composition of a magnetically permeable material
US6746310B2 (en) 2002-08-06 2004-06-08 Qed Technologies, Inc. Uniform thin films produced by magnetorheological finishing
US6893322B2 (en) 2001-05-22 2005-05-17 Qed Technologies, Inc. Method and apparatus for measuring and controlling solids composition of a magnetorheological fluid

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07198682A (ja) * 1993-12-28 1995-08-01 Kurita Water Ind Ltd 気泡検出装置
JP2000009414A (ja) * 1998-06-26 2000-01-14 Nippon Steel Corp 表層厚さ測定方法
JP3651268B2 (ja) * 1998-07-08 2005-05-25 学校法人金沢工業大学 磁気測定方法及び装置

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2790950A (en) * 1954-02-24 1957-04-30 United States Steel Corp Determining the permeability of magnetic material
USRE34039E (en) * 1985-09-30 1992-08-25 Kabushiki Kaisha Toshiba Torque sensor for detecting a shaft torque and an electric machine in which the torque sensor is mounted
US5554932A (en) 1993-12-17 1996-09-10 Eastman Kodak Company Measurement of a saturation magnetic flux density through use of a rotating permanent magnet
US5971835A (en) 1998-03-25 1999-10-26 Qed Technologies, Inc. System for abrasive jet shaping and polishing of a surface using magnetorheological fluid
US20030020463A1 (en) * 2001-05-11 2003-01-30 Lord Corporation System and method for monitoring the composition of a magnetically permeable material
US6650108B2 (en) 2001-05-11 2003-11-18 Lord Corporation System and method for monitoring the composition of a magnetorheological fluid
US6893322B2 (en) 2001-05-22 2005-05-17 Qed Technologies, Inc. Method and apparatus for measuring and controlling solids composition of a magnetorheological fluid
US6746310B2 (en) 2002-08-06 2004-06-08 Qed Technologies, Inc. Uniform thin films produced by magnetorheological finishing

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090267596A1 (en) * 2008-03-07 2009-10-29 California Institute Of Technology Effective-inductance-change based magnetic particle sensing
US9176206B2 (en) * 2008-03-07 2015-11-03 California Institute Of Technology Effective-inductance-change based magnetic particle sensing
US20100101309A1 (en) * 2008-10-23 2010-04-29 Simone Klyamkin System and method for measuring the concentration of magnetic ballast in a moving slurry
US8088284B2 (en) * 2008-10-23 2012-01-03 Cambridge Water Technology, Inc. System and method for measuring the concentration of magnetic ballast in a moving slurry
US9599591B2 (en) 2009-03-06 2017-03-21 California Institute Of Technology Low cost, portable sensor for molecular assays
EP2697017A4 (en) * 2011-04-13 2014-10-01 Qed Technologies Int Inc METHOD AND DEVICE FOR MEASURING AND CONTROLLING THE CONCENTRATION OF MAGNETIC PARTICLES IN A MAGNETORHEOLOGIC LIQUID
US20150233867A1 (en) * 2012-09-26 2015-08-20 Evoqua Water Technologies Llc System for Measuring the Concentration of Magnetic Ballast in a Slurry
US9651523B2 (en) * 2012-09-26 2017-05-16 Evoqua Water Technologies Llc System for measuring the concentration of magnetic ballast in a slurry
US20180292354A1 (en) * 2012-09-26 2018-10-11 Evoqua Water Technologies Llc System and Method for Measuring the Concentration of Magnetic Ballast in a Slurry

Also Published As

Publication number Publication date
US20080214092A1 (en) 2008-09-04
CN101622548A (zh) 2010-01-06
US20100079137A1 (en) 2010-04-01
US7888929B2 (en) 2011-02-15
JP2010520456A (ja) 2010-06-10
WO2008109301A1 (en) 2008-09-12

Similar Documents

Publication Publication Date Title
US7557566B2 (en) Method and apparatus for measurement of magnetic permeability of a material
Garaio et al. A wide-frequency range AC magnetometer to measure the specific absorption rate in nanoparticles for magnetic hyperthermia
DE4333419C2 (de) Verfahren und Vorrichtung zur Schichtdickenmessung und Meßsonde für eine kombinierte Schichtdickenmeßvorrichtung
JPS60194379A (ja) 磁界センサ及び磁界検出方法
US6650108B2 (en) System and method for monitoring the composition of a magnetorheological fluid
US2861242A (en) Magnetometer
Kraftmakher Eddy currents: Contactless measurement of electrical resistivity
Kordonski et al. In-line monitoring of (MR) fluid properties
Pshenichnikov A mutual-inductance bridge for analysis of magnetic fluids
JPS63134947A (ja) 磁化可能な物質の含有量を測定するための測定装置
Lebedev Measuring magnetization curves of ferrofluids: Comparison of the differential sweep method and a vibrating-sample magnetometer
Kraftmakher Measurement of electrical resistivity via the effective magnetic susceptibility
Blythe An automated technique for the measurement of the AC initial susceptibility and its disaccommodation in ferromagnetic materials
CN104483530A (zh) 高温超导块材表层临界电流密度不均匀性测量方法及装置
RU2170418C2 (ru) Способ определения концентрации ферромагнитных частиц в жидкости и магнитной восприимчивости в диапазоне свч
US3209246A (en) Magnetic field detector with a twocore flux gate magnetometer for a d.c. permeameter
Payet et al. Comparison between a magneto-optical method and Fannin's technique for the measurement of Brown's relaxation frequency of ferrofluids
Lu et al. Spin-density relaxation in superfluid A 1 3
Makhnovskiy et al. Surface impedance tensor in amorphous wires with helical anisotropy: Magnetic hysteresis and asymmetry
SU1656332A1 (ru) Способ измерени уровней нескольких жидкостей и устройство дл его осуществлени
RU2075758C1 (ru) Способ измерения напряженности магнитного поля
RU2322651C2 (ru) Способ градуировки и поверки электромагнитных расходомеров
Kratz et al. An ac method for measuring the specific heat of small probes and an application in the study on Gd2O2SO4
JPH02206757A (ja) セメント混合物中のセメント量の測定方法及び装置
Baker et al. The performance of electromagnetic flowmeters with magnetic slurries

Legal Events

Date Code Title Description
AS Assignment

Owner name: QED TECHNOLOGIES INTERNATIONAL, INC., ILLINOIS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KORDONSKI, WILLIAM;SEKERES, ARPAD;JAMES, ROBERT;REEL/FRAME:020422/0017

Effective date: 20070227

STCF Information on status: patent grant

Free format text: PATENTED CASE

AS Assignment

Owner name: BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT, IL

Free format text: NOTICE OF SECURITY INTEREST IN PATENTS;ASSIGNOR:CABOT MICROELECTRONICS CORPORATION;REEL/FRAME:027727/0275

Effective date: 20120213

FPAY Fee payment

Year of fee payment: 4

FPAY Fee payment

Year of fee payment: 8

AS Assignment

Owner name: CABOT MICROELECTRONICS CORPORATION, ILLINOIS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:BANK OF AMERICA, N.A.;REEL/FRAME:047587/0119

Effective date: 20181115

Owner name: JPMORGAN CHASE BANK, N.A., ILLINOIS

Free format text: SECURITY AGREEMENT;ASSIGNORS:CABOT MICROELECTRONICS CORPORATION;QED TECHNOLOGIES INTERNATIONAL, INC.;FLOWCHEM LLC;AND OTHERS;REEL/FRAME:047588/0263

Effective date: 20181115

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 12TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1553); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 12

AS Assignment

Owner name: CMC MATERIALS, INC., ILLINOIS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: INTERNATIONAL TEST SOLUTIONS, LLC, ILLINOIS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: SEALWELD (USA), INC., TEXAS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: MPOWER SPECIALTY CHEMICALS LLC, TEXAS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: KMG-BERNUTH, INC., TEXAS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: KMG ELECTRONIC CHEMICALS, INC., TEXAS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: FLOWCHEM LLC, TEXAS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: QED TECHNOLOGIES INTERNATIONAL, INC., NEW YORK

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: CABOT MICROELECTRONICS CORPORATION, ILLINOIS

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: CABOT MICROELECTRONICS CORPORATION, ILLINOIS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: QED TECHNOLOGIES INTERNATIONAL, INC., NEW YORK

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: FLOWCHEM LLC, TEXAS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: KMG ELECTRONIC CHEMICALS, INC., TEXAS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: KMG-BERNUTH, INC., TEXAS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: MPOWER SPECIALTY CHEMICALS LLC, TEXAS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: SEALWELD (USA), INC., TEXAS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: INTERNATIONAL TEST SOLUTIONS, LLC, ILLINOIS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

Owner name: CMC MATERIALS, INC., ILLINOIS

Free format text: RELEASE OF SECURITY INTEREST;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:060592/0260

Effective date: 20220706

AS Assignment

Owner name: MORGAN STANLEY SENIOR FUNDING, INC., AS COLLATERAL AGENT, MARYLAND

Free format text: SECURITY INTEREST;ASSIGNORS:CMC MATERIALS, INC.;INTERNATIONAL TEST SOLUTIONS, LLC;QED TECHNOLOGIES INTERNATIONAL, INC.;REEL/FRAME:060615/0001

Effective date: 20220706

Owner name: TRUIST BANK, AS NOTES COLLATERAL AGENT, NORTH CAROLINA

Free format text: SECURITY INTEREST;ASSIGNORS:ENTEGRIS, INC.;ENTEGRIS GP, INC.;POCO GRAPHITE, INC.;AND OTHERS;REEL/FRAME:060613/0072

Effective date: 20220706

AS Assignment

Owner name: QED TECHNOLOGIES INTERNATIONAL, INC., ILLINOIS

Free format text: PARTIAL RELEASE OF SECURITY INTEREST IN INTELLECTUAL PROPERTY RECORDED AT REEL 060613, FRAME 0072;ASSIGNOR:TRUIST BANK, AS NOTES COLLATERAL AGENT;REEL/FRAME:062901/0554

Effective date: 20230301

Owner name: QED TECHNOLOGIES INTERNATIONAL, INC., ILLINOIS

Free format text: PARTIAL RELEASE OF SECURITY INTEREST;ASSIGNOR:MORGAN STANLEY SENIOR FUNDING, INC., AS AGENT;REEL/FRAME:062904/0026

Effective date: 20230301

Owner name: FIDUS INVESTMENT CORPORATION, ILLINOIS

Free format text: SECURITY INTEREST;ASSIGNOR:QED TECHNOLOGIES INTERNATIONAL, INC.;REEL/FRAME:062838/0648

Effective date: 20230301